Free agency for the 2013 NFL season kicks off on Tuesday afternoon, and the Cleveland Browns are considered to be major players in the market.

Their nearly $50 million in salary cap space should likely mean the Browns will be quite active during free agency, as does the fact that the defense is switching to a 3-4 base this year and there are a number of talented free agents available who should make that transition go that much more smoothly.

Here's a comprehensive look at the Browns' free-agency activities this year, including roster additions and subtractions, re-signings, rumors and grades for every move of note they make.

Latest Rumors and Reports

Ezra Shaw/Getty ImagesCome Tuesday, Cliff Avril could be a Brown.

With so much money to spend and a seeming willingness to do so, the Browns have had free-agency rumors swirling about them for weeks now. With the event officially beginning on Tuesday afternoon, the din has only gotten louder.

March 18: Mary Kay Cabot of the Cleveland Plain Dealer reports that free agent cornerback Brent Grimes had a productive meeting with the Cleveland Browns this weekend and will make his decision about his next team later in the week.

March 13: Tom Reed of the Cleveland Plain Dealer reports that the Browns have given exclusive-rights free agent tenders to wide receiver Jordan Norwood and long snapper Christian Yount. The ERFA tender is worth $555,000.

March 13: Jason LaCanfora of CBS Sports says the Browns are interested in free agent tight end Fred Davis. Davis, however, has some risk associated with him, including a 2011 suspension and a 2012 Achilles' tendon tear.

March 13: Mary Kay Cabot of the Cleveland Plain Dealer reports that the Browns have signed linebacker Quentin Groves, who was formerly of the Arizona Cardinals where current Browns defensive coordinator Ray Horton used to hold the same title. It is a two-year deal worth $2.8 million.

March 11: Sports Illustrated's Peter King said in his "Monday Morning Quarterback" column that the Browns will be just as aggressive in free agency as has been expected and that they will likely land either Ravens linebacker Paul Kruger or Lions defensive end Cliff Avril to boost their pass rush. King believes they'll ultimately sign Avril on Tuesday evening.

March 9 (updated March 11): Mary Kay Cabot of the Cleveland Plain Dealer says that beyond Kruger, the Browns are also targeting another Ravens free-agent linebacker, Dannell Ellerbe. She adds that Cleveland is also interested in cornerbacks Antoine Cason and Greg Toler.

March 10: Lane Adkins of the Orange and Brown Report at Scout.com has a roundup of every rumor and non-starter that has circulated about the Browns since the start of the "legal tampering window" at midnight on Saturday. Among the gems:

The Browns won't be pursuing wide receiver Mike Wallace, who is likely to head to the Miami Dolphins.

While the Browns have been in contact with Ellerbe's agent, it looks like he'll be staying in Baltimore.

Cornerback Sean Smith is not on Cleveland's radar.

The Browns may look to see what recently released former Steelers linebacker James Harrison is looking for in a new contract.

The team has spoken with the agents for Patriots jack-of-all-trades Julian Edelman as well as Raiders tight end Brandon Myers.

At cornerback, the Browns have looked into both the Steelers' Keenan Lewis and the Eagles' Dominique Rodgers-Cromartie.

March 8: Two potential free-agent quarterbacks who may have been on the Browns' radar came off the market, with Matt Moore re-signing with the Miami Dolphins and Brian Hoyer staying on with the Arizona Cardinals.

March 1: Tony Grossi of ESPN Cleveland does not think the Browns will re-sign any of their impending free agents, which include Cribbs, tight ends Alex Smith and Watson and kicker Phil Dawson.

Roster Additions

Rob Carr/Getty ImagesCould Phil Dawson be re-signed?

The Browns have made no roster additions or re-signings in the days leading up to the start of free agency, which seems to point to Grossi's belief that the team has no interest in keeping around any of their own impending free agents.

Of their 18 combined restricted and unrestricted free agents, only kicker Phil Dawson has a high chance of being retained. The others will likely be allowed to move on.

Now that free agency has begun, the Browns have started to make moves.

Browns Sign LB Paul Kruger

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The Browns got the pass rusher they had been rumored to be pursuing when free agency began, signing Paul Kruger to a five-year deal worth a reported $40 million.

Kruger was the sack leader for the Super Bowl-winning Baltimore Ravens in 2012, and moved to a full-time role on the defense after spending the previous seasons as a pass rush specialist. This was a necessary move for the Browns, considering their need to improve their ability to attack the quarterback as well as their shift to a 3-4 defensive base.

Considering the cost—just $8 million per year—the Browns were able to get Kruger at a lower asking price than initially considered. It may also mean they aren't done adding pass rush talent this year, via either free agency or the draft.

Browns Sign DT Desmond Bryant

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The Browns continued to improve their defensive front seven via free agency, signing defensive tackle Desmond Bryant to a five-year, $34 million deal on Tuesday.

Bryant spent the last three seasons with the Oakland Raiders, where he racked up a total of 124 tackles, 10.5 sacks, three forced fumbles, one fumble recovery and a blocked kick. He played in all 16 games in 2012 and became the Raiders starting right tackle in Week 10, notching all of his sacks on the year once he took over the job.

He was Pro Football Focus' sixth-ranked defensive tackle for 2012, proving his strength as a pass rusher as well as a run defender, and he notched only two missed tackles on the year. His signing could mean that other Browns defensive linemen may be on the outs, but a front three that includes Bryant (possibly at nose tackle), Ahtyba Rubin and Phil Taylor is nothing to scoff at. Another smart move by the Browns.

Browns Sign LB Quentin Groves

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Quentin Groves is quite familiar with Ray Horton and his defense, so it makes sense why the Browns would want to bring on the former Arizona Cardinal.

Groves played 481 snaps in 2012 at both right and left outside linebacker in Horton's 3-4 defense and took over as starter on the left in Week 11. He notched four sacks, five quarterback hits and seven hurries last season.

He's more of a run-stopping outside linebacker than a pass rusher. Of those 441 snaps last year, 255 were against the run while only 144 were in pass rush. He was a situational run stopper who was thrown into the starting job last year and handled it well, but anticipate a return to situational work in Cleveland.

For $2.8 million over two years, it's a fair price for a Horton veteran.

Browns Sign TE Gary Barnidge

The Browns added tight end depth in a nod to their new head coach Rob Chudzinski by signing Carolina Panthers free agent Gary Barnidge to the roster on Wednesday. He signed a three-year deal.

Barnidge worked with Chudzinski while Chudzinski was the Panthers' offensive coordinator. He started in five games in 2012 and appeared in all 16, catching all six passes thrown his way for 78 yards and a touchdown.

Of his 140 snaps last year, 65 were as a receiver and 68 in run blocking. This may provide a hint of how he'll be used in Cleveland, but one also must remember he was second on the depth chart behind top-tier tight end Greg Olsen, which clearly limited Barnidge's targets.

Regardless of how many passes are thrown to him, the Browns certainly needed to add tight end depth. This is a utilitarian pickup and won't cost too much money. It also doesn't preclude them from bringing on yet another tight end via either free agency or the draft.